The present invention relates to a crankcase with integrated exhaust chambers.
In connection with the evacuation of oil by blow by, it is known from DE 197 36 040 A1 to place plenum chambers in communication with the oil evacuator in order to achieve a pre-evacuation of the largest drops of oil. Two plenum chambers are provided for this pre-evacuation step, each of which extends on a respective opposite side of the cylinder bores over the entire length of the crankcase. These plenum chambers are communicated via bores with the crank chamber. An evacuation arrangement of this type has serious disadvantages with respect to the technical aspects of manufacturing such an arrangement. A multitude of casting core hole covers are required on the side walls of the crankcase for removing the casting sand used for the manufacturing of the plenum chambers.
The present invention provides a solution to the challenge of manufacturing the above-noted type of plenum chambers in a manner which is advantageous from the point of view of casting of the plenum chambers.
In view of the fact that there is ready access to the side plenum chambers via the bore for the sleeve or cylinder liner, the casting core for casting the plenum chambers can be configured as an integral piece with the crank chamber casting core and the casting sand can be easily removed. Casting core hole covers in the side walls of the crankcase can be completely dispensed with.
The integral configuration of the casting cores as a single unit ensures an efficient manufacturing of the crankcase.